Security officials patrol at the bomb blast site in southwest Pakistan on Dec. 30, 2012.
Hundreds of men and women have staged a demonstration in the western Pakistan city of Quetta to express their outrage over the killings of Shia Muslims in the country.
On Sunday, the protesters called on the government to take immediate action against the forces involved in the sectarian killings and said more demonstrations would be staged if justice is not served.
Demonstrations were also held in the cities of Multan and Karachi, where protesters chanted slogans condemning the killings.
Earlier in the day, a terrorist attack on Shia pilgrims claimed the lives of 19 people in southwestern Pakistan as the pilgrims were on their way to Iran.
The pilgrims died when a car full of explosives hit their convoy in the Mastung district, about 30 kilometers (18 miles) south of Quetta, the capital of the Baluchistan province.
Reports said a number of women and children were among the dead.
According to Human Rights Watch, at least 320 Shia Muslims were killed in 2012 in Pakistan.
The New York-based group said Islamabad's failure to capture or prosecute terrorists suggested it was "indifferent" towards the killings.
Human rights groups in Pakistan have vehemently criticized the government for its failure to stem the rising tide of violence against the country’s Shia Muslims.
Anti-Shia militant groups have been engaged in a violent campaign against Shias over the past few years.
Pakistani Shia leaders have called on the government to form a judicial commission to investigate the violence against Shias, who account for around 20 percent of the country’s 180-million-strong population.